the radiation from japan is no risk. >> we don't expect it to have any effect on health. >> reporter: the same with tap water. it is no added risk. but researchers are excited by these findings building this new did he deck tore to expand their monitoring of air, water and milk. >> using radioactivity to tell us how the particles distribute in our environment and there is a unique opportunity as researchers to do that. >> reporter: scientists say there is no health risk today. but by tracking these isotopes today they will be better prepared if there is a major release in the future. health and science editor john fowler, ktvu, channel 2 news. >>> the u.s. congress today pressed regulatory officials for answers on the safety of america's nuclear plants and their spent nuclear fuel rods. diane finestein said she recent live toured the canyon's power plant. she learned that spent fuel rods are stored in pools similar to those leaking radiation at the damaged japanese plant. one expert said that's common practice in the u.s. >> the pools are often housed in buildings with sheet metal sid